HACEK organisms were isolated from 35 (<0.005%) of 59,203 positive blood cultures. None of 407 blood cultures with extended incubation grew HACEK or other bacteria. Bacteremia from HACEK bacteria is rare, and extended incubation of blood cultures to recover HACEK bacteria is unnecessary.

Can you culture HACEK?

The HACEK group accounts for approximately 5%-10% of community-acquired native-valve endocarditis cases in patients who do not use intravenous drugs. HACEK microorganisms grow slowly in standard blood culture media, and recovery may require prolonged incubation.

How do you identify HACEK organisms?

HACEK organisms are not readily identified on most automated bacterial identification systems, and most require either time-consuming biochemical profiling or genetic analysis, such as 16S rRNA gene sequencing, for definitive identification (8).

Are HACEK culture-negative?

The HACEK organisms are a group of fastidious Gram-negative bacteria that are an unusual cause of infective endocarditis, which is an inflammation of the heart due to bacterial infection.

What is bacterial group HACEK?

The HACEK group of bacteria (Haemophilus species, Aggregatibacter species, Cardiobacterium hominis, Eikenella corrodens, and Kingella species) are a small, heterogeneous group of fastidious, gram-negative bacteria that frequently colonize the oropharynx and have long been recognised as a cause of infective endocarditis …

How do you treat HACEK?

Ceftriaxone is reasonable for treatment of HACEK IE. Four weeks of therapy for HACEK native-valve endocarditis is reasonable; for HACEK prosthetic valve endocarditis, a therapy duration of 6 weeks is reasonable. Gentamicin is not recommended because of its nephrotoxicity risks.

Can you have endocarditis with negative blood cultures?

Blood culture-negative endocarditis (BCNE), that is, endocarditis in which blood cultures using usual laboratory methods remain sterile, may account for 2.5% to 70% of all cases of endocarditis, depending on countries.

How do you test for HACEK?

Clinical Identification of HACEK Organisms However, modern blood culture instruments reliably detect HACEK organisms within a 5-day incubation period. HACEK organisms can be isolated on routinely used non-selective media, often growing better on chocolate agar than on blood agar.